Assertion : A force act upon the earth revolving in a circular orbit about the sun. Hence work should be done on the earth. Reason : The necessary centripetal force for circular motion of earth comes from the gravitational force between earth and sun.

(a)       If both assertion and reason are true and the reason is the correct explanation of the assertion.

(b)       If both assertion and reason are true but reason is not the correct explanation of the assertion.

(c)        If assertion is true but reason is false.

(d)       If the assertion and reason both are false.

(e)       If assertion is false but reason is true.

Answer: e

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